Dynamic ue-category switching for enhanced idle mode power savings

ABSTRACT

Certain aspects of the present disclosure relate to methods and apparatus for dynamic UE-Category switching for enhanced idle mode power savings. A method for wireless communications by a user equipment (UE) is provided. The method generally includes, determining that a cell supports a second UE category, lower than a first UE category; and while in an idle mode: operating in the cell according to the first UE category; and taking action to operate in the cell according to the second UE category based on the determination.

CROSS REFERENCE TO RELATED APPLICATION

This application is a divisional application of U.S. patent applicationSer. No. 15/417,485, filed Jan. 27, 2017, having U.S. patent Ser. No.10/728,741 with an issue date of Jan. 28, 2020, and assigned to theassignee hereof.

FIELD OF THE DISCLOSURE

The present disclosure relates generally to communication systems, andmore particularly, to methods and apparatus for dynamic UE-Categoryswitching for enhanced idle mode power savings.

DESCRIPTION OF RELATED ART

Wireless communication systems are widely deployed to provide varioustelecommunication services such as telephony, video, data, messaging,and broadcasts. Typical wireless communication systems may employmultiple-access technologies capable of supporting communication withmultiple users by sharing available system resources (e.g., bandwidth,transmit power). Examples of such multiple-access technologies includecode division multiple access (CDMA) systems, time division multipleaccess (TDMA) systems, frequency division multiple access (FDMA)systems, orthogonal frequency division multiple access (OFDMA) systems,single-carrier frequency divisional multiple access (SC-FDMA) systems,time division synchronous code division multiple access (TD-SCDMA)systems, and Long Term Evolution (LTE). LTE/LTE-Advanced is a set ofenhancements to the Universal Mobile Telecommunications System (UMTS)mobile standard promulgated by Third Generation Partnership Project(3GPP).

A wireless communication network may include a number of base stations(BS) that can support communication for a number of user equipments(UEs). A UE may communicate with a BS via the downlink and uplink. Thedownlink (or forward link) refers to the communication link from the BSto the UE, and the uplink (or reverse link) refers to the communicationlink from the UE to the BS. As will be described in more detail herein,a BS may be referred to as a Node B, a gNB, access point (AP), radiohead, TRP (transmit receive point, transmission reception point, etc.),new radio (NR) BS, 5G NB, etc.

These multiple access technologies have been adopted in varioustelecommunication standards to provide a common protocol that enablesdifferent wireless devices to communicate on a municipal, national,regional, and even global level. New radio (NR), which may also bereferred to as 5G, is a set of enhancements to the LTE mobile standardpromulgated by Third Generation Partnership Project (3GPP). It isdesigned to better support mobile broadband Internet access by improvingspectral efficiency, lower costs, improve services, make use of newspectrum, and better integrate with other open standards using OFDMAwith a cyclic prefix (CP) on the downlink (DL) and on the uplink (UL) aswell as support beamforming, multiple-input multiple-output (MIMO)antenna technology, and carrier aggregation. However, as the demand formobile broadband access continues to increase, there exists a need forfurther improvements in LTE, NR, and 5G technologies. Preferably, theseimprovements should be applicable to other multi-access technologies andthe telecommunication standards that employ these technologies.

SUMMARY

The systems, methods, and devices of the disclosure each have severalaspects, no single one of which is solely responsible for its desirableattributes. Without limiting the scope of this disclosure as expressedby the claims which follow, some features will now be discussed briefly.After considering this discussion, and particularly after reading thesection entitled “DETAILED DESCRIPTION” one will understand how thefeatures of this disclosure provide advantages that include improvedcommunications between access points and stations in a wireless network.

Aspects of the present disclosure relate to methods and apparatus fordynamic UE-Category switching for enhanced idle mode power savings.

Certain aspects of the present disclosure provide a method for wirelesscommunications by a user equipment (UE). The method generally includesdetermining that a cell supports a second UE category, lower than afirst UE category; and while in an idle mode: operating in the cellaccording to the first UE category; and taking action to operate in thecell according to the second UE category.

Certain aspects of the present disclosure provide an apparatus forwireless communications by a UE. The apparatus generally includes meansfor determining that a cell supports a second UE category, lower than afirst UE category; means for, while in an idle mode, operating in thecell according to the first UE category; and means for, while in theidle mode, taking action to operate in the cell according to the secondUE category.

Certain aspects of the present disclosure provide an apparatus forwireless communications by a UE. The apparatus generally includes atleast one processor and a memory coupled to the at least one processor.The at least one processor is generally configured to determine that acell supports a second UE category, lower than a first UE category; andwhile in an idle mode: operate in the cell according to the first UEcategory; and take action to operate in the cell according to the secondUE category.

Certain aspects of the present disclosure provide a computer readablemedium having computer executable code stored thereon for wirelesscommunications by a UE. The computer executable code generally includescode for determining that the cell supports a second UE category, lowerthan a first UE category; code for, while in an idle mode, operating inthe cell according to the first UE category; and code for, while in theidle mode, taking action to operate in the cell according to the secondUE category.

Certain aspects of the present disclosure provide a method for wirelesscommunications by a base station (BS). The method generally includesbroadcasting information indicating that the BS supports a second UEcategory, lower than a first UE category; and receiving combinedregistration information registering a UE as the first UE category andthe second UE category.

Certain aspects of the present disclosure provide an apparatus forwireless communications by a BS. The apparatus generally includes meansfor broadcasting information indicating that the BS supports a second UEcategory, lower than a first UE category; and means for receivingcombined registration information registering a UE as the first UEcategory and the second UE category.

Certain aspects of the present disclosure provide an apparatus forwireless communications by a BS. The apparatus generally includes atleast one processor and a memory coupled to the at least one processor.The at least one processor is generally configured to broadcastinformation indicating that the BS supports a second UE category, lowerthan a first UE category; and receive combined registration informationregistering the UE as the first UE category and the second UE category.

Certain aspects of the present disclosure provide a computer readablemedium having computer executable code stored thereon for wirelesscommunications by a BS. The computer executable code generally includescode for broadcasting information indicating that the BS supports asecond UE category, lower than a first UE category; and code forreceiving combined registration information registering the UE as thefirst UE category and the second UE category.

Other aspects, features, and aspects of the present disclosure willbecome apparent to those of ordinary skill in the art, upon reviewingthe following description of specific, exemplary aspects of the presentdisclosure in conjunction with the accompanying figures. While featuresof the present disclosure may be discussed relative to certain aspectsand figures below, all aspects of the present disclosure can include oneor more of the advantageous features discussed herein. In other words,while one or more aspects may be discussed as having certainadvantageous features, one or more of such features may also be used inaccordance with the various aspects of the invention disclosure herein.In similar fashion, while exemplary aspects may be discussed below asdevice, system, or method aspects it should be understood that suchexemplary aspects can be implemented in various devices, systems,methods, and computer readable media.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above-recited features of the presentdisclosure can be understood in detail, a more particular description,briefly summarized above, may be had by reference to aspects, some ofwhich are illustrated in the appended drawings. The appended drawingsillustrate only certain typical aspects of this disclosure, however, andare therefore not to be considered limiting of its scope, for thedescription may admit to other equally effective aspects.

FIG. 1 is a block diagram conceptually illustrating an example of awireless communication network, in accordance with certain aspects ofthe present disclosure.

FIG. 2 shows a block diagram conceptually illustrating an example of abase station in communication with a user equipment (UE) in a wirelesscommunications network, in accordance with certain aspects of thepresent disclosure.

FIG. 3 is a block diagram conceptually illustrating an example of aframe structure in a wireless communications network, in accordance withcertain aspects of the present disclosure.

FIG. 4 is a block diagram conceptually illustrating two exemplarysubframe formats with the normal cyclic prefix, in accordance withcertain aspects of the present disclosure.

FIG. 5 illustrates an example logical architecture of a distributedradio access network (RAN), in accordance with certain aspects of thepresent disclosure.

FIG. 6 illustrates an example physical architecture of a distributedRAN, in accordance with certain aspects of the present disclosure.

FIG. 7 is a diagram illustrating an example of a downlink (DL)-centricsubframe, in accordance with certain aspects of the present disclosure.

FIG. 8 is a diagram illustrating an example of an uplink (UL)-centricsubframe, in accordance with certain aspects of the present disclosure.

FIG. 9 is a flow diagram illustrating operations performed by a UE fordynamically switching UE-Category, in accordance with certain aspects ofthe present disclosure.

FIG. 10 is a flow diagram illustrating operations performed by a BS fordynamically switching UE-Category, in accordance with certain aspects ofthe present disclosure.

FIG. 11 is a call flow diagram for dynamically switching UE-Category, inaccordance with certain aspects of the present disclosure.

FIG. 12 is another call flow diagram for dynamically switchingUE-Category, in accordance with certain aspects of the presentdisclosure.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe figures. It is contemplated that elements disclosed in one aspectmay be beneficially utilized on other aspects without specificrecitation.

DETAILED DESCRIPTION

As will be described in more detail below, a user equipment (UE) maysupport various UE-categories (e.g., long term evolution (LTE)UE-categories, 5G UE-categories, etc.). The different UE-categories maydefine uplink and downlink operating parameters for the UE. SomeUE-categories may use less power than other UE-categories. It may bedesirable for an idle mode UE to operate according to a UE-category thatuses less power than a UE-category in the connected mode.

Aspects of the present disclosure provide techniques and apparatus fordynamic UE-Category switching for enhanced idle mode power savings. Forexample, if the cell supports a lower UE-category, such Cat-M1, the UEmay dynamically switch to the lower UE-category when the UE moves to theidle mode or after the UE is in the idle mode for a duration. In somecases, the UE may initiate an out-of-service procedure and thenre-register as the lower UE-category. Alternatively, during an initialattach procedure to the cell, the UE may register as both the higher andlower UE-category.

Various aspects of the disclosure are described more fully hereinafterwith reference to the accompanying drawings. This disclosure may,however, be embodied in many different forms and should not be construedas limited to any specific structure or function presented throughoutthis disclosure. Rather, these aspects are provided so that thisdisclosure will be thorough and complete, and will fully convey thescope of the disclosure to those skilled in the art. Based on theteachings herein one skilled in the art should appreciate that the scopeof the disclosure is intended to cover any aspect of the disclosuredisclosed herein, whether implemented independently of or combined withany other aspect of the disclosure. For example, an apparatus may beimplemented or a method may be practiced using any number of the aspectsset forth herein. In addition, the scope of the disclosure is intendedto cover such an apparatus or method which is practiced using otherstructure, functionality, or structure and functionality in addition toor other than the various aspects of the disclosure set forth herein. Itshould be understood that any aspect of the disclosure disclosed hereinmay be embodied by one or more elements of a claim. The word “exemplary”is used herein to mean “serving as an example, instance, orillustration.” Any aspect described herein as “exemplary” is notnecessarily to be construed as preferred or advantageous over otheraspect. Several aspects of telecommunication systems will now bepresented with reference to various apparatus and methods. Theseapparatus and methods will be described in the following detaileddescription and illustrated in the accompanying drawings by variousblocks, modules, components, circuits, steps, processes, algorithms,etc. (collectively referred to as “elements”). These elements may beimplemented using hardware, software, or combinations thereof. Whethersuch elements are implemented as hardware or software depends upon theparticular application and design constraints imposed on the overallsystem.

An access point (“AP”) may comprise, be implemented as, or known asNodeB, Radio Network Controller (“RNC”), eNodeB (eNB), Base StationController (“BSC”), Base Transceiver Station (“BTS”), Base Station(“BS”), Transceiver Function (“TF”), Radio Router, Radio Transceiver,Basic Service Set (“BSS”), Extended Service Set (“ESS”), Radio BaseStation (“RBS”), Node B (NB), gNB, 5G NB, NR BS, Transmit Receive Point(TRP), or some other terminology.

An access terminal (“AT”) may comprise, be implemented as, or be knownas an access terminal, a subscriber station, a subscriber unit, a mobilestation, a remote station, a remote terminal, a user terminal, a useragent, a user device, user equipment (UE), a user station, a wirelessnode, or some other terminology. In some implementations, an accessterminal may comprise a cellular telephone, a smart phone, a cordlesstelephone, a Session Initiation Protocol (“SIP”) phone, a wireless localloop (“WLL”) station, a personal digital assistant (“PDA”), a handhelddevice having wireless connection capability, a Station (“STA”), or someother suitable processing device connected to a wireless modem.Additional examples of access terminals include a computer (e.g., adesktop), a portable communication device, a portable computing device(e.g., a laptop, a personal data assistant, a tablet, a netbook, asmartbook, an ultrabook), wearable device (e.g., smart watch, smartglasses, virtual reality goggles, smart bracelet, smart wristband, smartbelt, smart ring, smart jewelry, smart clothing, etc.), medical devicesor equipment, healthcare device, biometric sensors/devices, anentertainment device (e.g., music device, video device, satellite radio,gaming device, etc.), a camera, a vehicular component or sensor, smartmeters/sensors, industrial manufacturing equipment, a positioning device(e.g., GPS, Beidou, etc.), a drone, a robot/robotic device, or any othersuitable device that is configured to communicate via a wireless orwired medium. In some aspects, a node is a wireless node. A wirelessnode may provide, for example, connectivity for or to a network (e.g., awide area network such as the Internet or a cellular network) via awired or wireless communication link. Some UEs may be consideredmachine-type communication (MTC) or enhanced MTC (eMTC) UEs, which mayinclude remote devices that may communicate with a base station, anotherremote device, or some other entity. Machine type communications (MTC)may refer to communication involving at least one remote device on atleast one end of the communication and may include forms of datacommunication which involve one or more entities that do not necessarilyneed human interaction. MTC UEs may include UEs that are capable of MTCcommunications with MTC servers and/or other MTC devices through PublicLand Mobile Networks (PLMN), for example. Examples of MTC devicesinclude sensors, meters, location tags, monitors, drones, robots/roboticdevices, etc. MTC UEs, as well as other types of UEs, may be implementedas narrowband Internet-of-Things (NB-IoT) devices.

It is noted that while aspects may be described herein using terminologycommonly associated with 3G and/or 4G wireless technologies, aspects ofthe present disclosure can be applied in other generation-basedcommunication systems, such as 5G and later, including new radio (NR)technologies.

An Example Wireless Communication System

FIG. 1 is a diagram illustrating an architecture for a wirelesscommunication network 100 in which aspects of the present disclosure maybe practiced. For example, the UE 120 may operate according to a firstUE category (e.g., regular UE CAT) in the idle mode. The UE 120 maydetermine that the cell (e.g., BS 110) supports a second UE category(e.g., UE CAT M1) lower than the first UE category. The UE 120 may takeaction to operate in the cell according to the second UE category.

Wireless communication network 100 may be an LTE network or some otherwireless network, such as a 5G or new radio (NR) network. Wirelesscommunication network 100 may include a number of BSs 110 and othernetwork entities. A BS is an entity that communicates with userequipments (UEs) and may also be referred to as a NR BS, a Node B (NB),a gNB, a 5G NB, an access point (AP), a transmit receive point (TRP),etc. Each BS may provide communication coverage for a particulargeographic area. In 3GPP, the term “cell” can refer to a coverage areaof a BS and/or a BS subsystem serving this coverage area, depending onthe context in which the term is used.

A BS may provide communication coverage for a macro cell, a pico cell, afemto cell, and/or other types of cell. A macro cell may cover arelatively large geographic area (e.g., several kilometers in radius)and may allow unrestricted access by UEs with service subscription. Apico cell may cover a relatively small geographic area and may allowunrestricted access by UEs with service subscription. A femto cell maycover a relatively small geographic area (e.g., a home) and may allowrestricted access by UEs having association with the femto cell (e.g.,UEs in a closed subscriber group (CSG)). A BS for a macro cell may bereferred to as a macro BS. A BS for a pico cell may be referred to as apico BS. A BS for a femto cell may be referred to as a femto BS or ahome BS. In the example shown in FIG. 1, a BS 110 a may be a macro BSfor a macro cell 102 a, an BS 110 b may be a pico BS for a pico cell 102b, and a BS 110 c may be a femto BS for a femto cell 102 c. A BS maysupport one or multiple (e.g., three) cells. The terms “eNB”, “basestation”, “NR BS”, “gNB”, “TRP”, “AP”, “node B”, “5G NB”, “wirelessnode”, and “cell” may be used interchangeably herein.

In some examples, a cell may not necessarily be stationary, and thegeographic area of the cell may move according to the location of amobile base station. In some examples, the base stations may beinterconnected to one another and/or to one or more other base stationsor network nodes (not shown) in the access network 100 through varioustypes of backhaul interfaces such as a direct physical connection, avirtual network, or the like using any suitable transport network.

Wireless communication network 100 may also include relay stations. Arelay station is an entity that can receive a transmission of data froman upstream station (e.g., a BS or a UE) and send a transmission of thedata to a downstream station (e.g., a UE or a BS). A relay station mayalso be a UE that can relay transmissions for other UEs. In the exampleshown in FIG. 1, a relay station 110 d may communicate with macro BS 110a and a UE 120 d in order to facilitate communication between BS 110 aand UE 120 d. A relay station may also be referred to as a relay BS, arelay base station, a relay, etc.

Wireless communication network 100 may be a heterogeneous network thatincludes BSs of different types, e.g., macro BSs, pico BSs, femto BSs,relay BSs, etc. These different types of BSs may have different transmitpower levels, different coverage areas, and different impact oninterference in wireless communication network 100. For example, macroBSs may have a high transmit power level (e.g., 5 to 40 Watts) whereaspico BSs, femto BSs, and relay BSs may have lower transmit power levels(e.g., 0.1 to 2 Watts).

A network controller 130 may couple to a set of BSs and may providecoordination and control for these BSs. Network controller 130 maycommunicate with the BSs via a backhaul. The BSs may also communicatewith one another, e.g., directly or indirectly via a wireless orwireline backhaul.

UEs 120 (e.g., 120 a, 120 b, 120 c) may be dispersed throughout wirelessnetwork 100, and each UE may be stationary or mobile. A UE may also bereferred to as an access terminal, a terminal, a mobile station, asubscriber unit, a station, etc. A UE may be a cellular phone (e.g., asmart phone), a personal digital assistant (PDA), a wireless modem, awireless communication device, a handheld device, a laptop computer, acordless phone, a wireless local loop (WLL) station, a tablet, a camera,a gaming device, a netbook, a smartbook, an ultrabook, medical device orequipment, biometric sensors/devices, wearable devices (smart watches,smart clothing, smart glasses, smart wrist bands, smart jewelry (e.g.,smart ring, smart bracelet)), an entertainment device (e.g., a music orvideo device, or a satellite radio), a vehicular component or sensor,smart meters/sensors, industrial manufacturing equipment, a globalpositioning system device, or any other suitable device that isconfigured to communicate via a wireless or wired medium. Some UEs maybe considered evolved or enhanced machine-type communication (eMTC) UEs.MTC and eMTC UEs include, for example, robots, drones, remote devices,such as sensors, meters, monitors, location tags, etc., that maycommunicate with a base station, another device (e.g., remote device),or some other entity. A wireless node may provide, for example,connectivity for or to a network (e.g., a wide area network such asInternet or a cellular network) via a wired or wireless communicationlink. Some UEs may be considered Internet-of-Things (IoT) devices ornarrowband IoT (NB-IoT) devices. Some UEs may be considered a CustomerPremises Equipment (CPE).

In FIG. 1, a solid line with double arrows indicates desiredtransmissions between a UE and a serving BS, which is a BS designated toserve the UE on the downlink and/or uplink. A dashed line with doublearrows indicates potentially interfering transmissions between a UE anda BS.

In general, any number of wireless networks may be deployed in a givengeographic area. Each wireless network may support a particular RAT andmay operate on one or more frequencies. A RAT may also be referred to asa radio technology, an air interface, etc. A frequency may also bereferred to as a carrier, a frequency channel, etc. Each frequency maysupport a single RAT in a given geographic area in order to avoidinterference between wireless networks of different RATs. In some cases,NR or 5G RAT networks may be deployed.

In some examples, access to the air interface may be scheduled, whereina scheduling entity (e.g., a base station) allocates resources forcommunication among some or all devices and equipment within its servicearea or cell. Within the present disclosure, as discussed further below,the scheduling entity may be responsible for scheduling, assigning,reconfiguring, and releasing resources for one or more subordinateentities. That is, for scheduled communication, subordinate entitiesutilize resources allocated by the scheduling entity.

Base stations are not the only entities that may function as ascheduling entity. That is, in some examples, a UE may function as ascheduling entity, scheduling resources for one or more subordinateentities (e.g., one or more other UEs). In this example, the UE isfunctioning as a scheduling entity, and other UEs utilize resourcesscheduled by the UE for wireless communication. A UE may function as ascheduling entity in a peer-to-peer (P2P) network, and/or in a meshnetwork. In a mesh network example, UEs may optionally communicatedirectly with one another in addition to communicating with thescheduling entity.

Thus, in a wireless communication network with a scheduled access totime-frequency resources and having a cellular configuration, a P2Pconfiguration, and a mesh configuration, a scheduling entity and one ormore subordinate entities may communicate utilizing the scheduledresources.

FIG. 2 shows a block diagram of a design of BS 110 and UE 120, which maybe one of the BSs and one of the UEs in FIG. 1. BS 110 may be equippedwith T antennas 234 a through 234 t, and UE 120 may be equipped with Rantennas 252 a through 252 r, where in general T≥1 and R≥1.

At BS 110, a transmit processor 220 may receive data from a data source212 for one or more UEs, select one or more modulation and codingschemes (MCS) for each UE based on CQIs received from the UE, process(e.g., encode and modulate) the data for each UE based on the MCS(s)selected for the UE, and provide data symbols for all UEs. Transmitprocessor 220 may also process system information (e.g., for SRPI, etc.)and control information (e.g., CQI requests, grants, upper layersignaling, etc.) and provide overhead symbols and control symbols.Processor 220 may also generate reference symbols for reference signals(e.g., the CRS) and synchronization signals (e.g., the PSS and SSS). Atransmit (TX) multiple-input multiple-output (MIMO) processor 230 mayperform spatial processing (e.g., precoding) on the data symbols, thecontrol symbols, the overhead symbols, and/or the reference symbols, ifapplicable, and may provide T output symbol streams to T modulators(MODs) 232 a through 232 t. Each modulator 232 may process a respectiveoutput symbol stream (e.g., for OFDM, etc.) to obtain an output samplestream. Each modulator 232 may further process (e.g., convert to analog,amplify, filter, and upconvert) the output sample stream to obtain adownlink signal. T downlink signals from modulators 232 a through 232 tmay be transmitted via T antennas 234 a through 234 t, respectively.According to certain aspects described in more detail below, thesynchronization signals can be generated with location encoding toconvey additional information.

At UE 120, antennas 252 a through 252 r may receive the downlink signalsfrom base station 110 and/or other base stations and may providereceived signals to demodulators (DEMODs) 254 a through 254 r,respectively. Each demodulator 254 may condition (e.g., filter, amplify,downconvert, and digitize) its received signal to obtain input samples.Each demodulator 254 may further process the input samples (e.g., forOFDM, etc.) to obtain received symbols. A MIMO detector 256 may obtainreceived symbols from all R demodulators 254 a through 254 r, performMIMO detection on the received symbols if applicable, and providedetected symbols. A receive processor 258 may process (e.g., demodulateand decode) the detected symbols, provide decoded data for UE 120 to adata sink 260, and provide decoded control information and systeminformation to a controller/processor 280. A channel processor maydetermine RSRP, RSSI, RSRQ, CQI, etc.

On the uplink, at UE 120, a transmit processor 264 may receive andprocess data from a data source 262 and control information (e.g., forreports comprising RSRP, RSSI, RSRQ, CQI, etc.) fromcontroller/processor 280. Processor 264 may also generate referencesymbols for one or more reference signals. The symbols from transmitprocessor 264 may be precoded by a TX MIMO processor 266 if applicable,further processed by modulators 254 a through 254 r (e.g., for SC-FDM,OFDM, etc.), and transmitted to base station 110. At BS 110, the uplinksignals from UE 120 and other UEs may be received by antennas 234,processed by demodulators 232, detected by a MIMO detector 236 ifapplicable, and further processed by a receive processor 238 to obtaindecoded data and control information sent by UE 120. Processor 238 mayprovide the decoded data to a data sink 239 and the decoded controlinformation to controller/processor 240. BS 110 may includecommunication unit 244 and communicate to network controller 130 viacommunication unit 244. Network controller 130 may include communicationunit 294, controller/processor 290, and memory 292.

Controllers/processors 240 and 280 and/or any other component(s) in FIG.2 may direct the operation at base station 110 and UE 120, respectively,to perform techniques presented herein for MSI decoding using an offlineor online mode. For example, processor 280 and/or other processors andmodules at UE 120, may perform or direct operations of UE 120 to performtechniques presented herein for dynamic switching of UE-Category. Forexample, controller/processor 280 and/or other controllers/processorsand modules at UE 120 may perform or direct operations 900 shown in FIG.9. For example, controller/processor 240 and/or othercontrollers/processors and modules at base station 110 may perform ordirect operations 1000 shown in FIG. 10. Memories 242 and 282 may storedata and program codes for base station 110 and UE 120, respectively. Ascheduler 246 may schedule UEs for data transmission on the downlinkand/or uplink.

FIG. 3 shows an exemplary frame structure 300 for FDD in atelecommunications system (e.g., LTE). The transmission timeline foreach of the downlink and uplink may be partitioned into units of radioframes. Each radio frame may have a predetermined duration (e.g., 10milliseconds (ms)) and may be partitioned into 10 subframes with indicesof 0 through 9. Each subframe may include two slots. Each radio framemay thus include 20 slots with indices of 0 through 19. Each slot mayinclude L symbol periods, e.g., seven symbol periods for a normal cyclicprefix (as shown in FIG. 3) or six symbol periods for an extended cyclicprefix. The 2L symbol periods in each subframe may be assigned indicesof 0 through 2L−1.

In certain telecommunications (e.g., LTE), a BS may transmit a primarysynchronization signal (PSS) and a secondary synchronization signal(SSS) on the downlink in the center of the system bandwidth for eachcell supported by the BS. The PSS and SSS may be transmitted in symbolperiods 6 and 5, respectively, in subframes 0 and 5 of each radio framewith the normal cyclic prefix, as shown in FIG. 3. The PSS and SSS maybe used by UEs for cell search and acquisition. The BS may transmit acell-specific reference signal (CRS) across the system bandwidth foreach cell supported by the BS. The CRS may be transmitted in certainsymbol periods of each subframe and may be used by the UEs to performchannel estimation, channel quality measurement, and/or other functions.The BS may also transmit a physical broadcast channel (PBCH) in symbolperiods 0 to 3 in slot 1 of certain radio frames. The PBCH may carrysome system information. The BS may transmit other system informationsuch as system information blocks (SIB s) on a physical downlink sharedchannel (PDSCH) in certain subframes. The BS may transmit controlinformation/data on a physical downlink control channel (PDCCH) in thefirst B symbol periods of a subframe, where B may be configurable foreach subframe. The BS may transmit traffic data and/or other data on thePDSCH in the remaining symbol periods of each subframe.

In other systems (e.g., such NR or 5G systems), the BS may transmitthese or other signals in these locations or in different locations ofthe subframe.

FIG. 4 shows two exemplary subframe formats 410 and 420 with the normalcyclic prefix. The available time frequency resources may be partitionedinto resource blocks (RBs). Each RB may cover 12 subcarriers in one slotand may include a number of resource elements (REs). Each RE may coverone subcarrier in one symbol period and may be used to send onemodulation symbol, which may be a real or complex value.

Subframe format 410 may be used for two antennas. A CRS may betransmitted from antennas 0 and 1 in symbol periods 0, 4, 7 and 11. Areference signal (RS) is a signal that is known a priori by atransmitter and a receiver and may also be referred to as pilot. A CRSis a RS that is specific for a cell, e.g., generated based on a cellidentity (ID). In FIG. 4, for a given RE with label Ra, a modulationsymbol may be transmitted on that RE from antenna a, and no modulationsymbols may be transmitted on that RE from other antennas. Subframeformat 420 may be used with four antennas. A CRS may be transmitted fromantennas 0 and 1 in symbol periods 0, 4, 7 and 11 and from antennas 2and 3 in symbol periods 1 and 8. For both subframe formats 410 and 420,a CRS may be transmitted on evenly spaced subcarriers, which may bedetermined based on cell ID. CRSs may be transmitted on the same ordifferent subcarriers, depending on their cell IDs. For both subframeformats 410 and 420, REs not used for the CRS may be used to transmitdata (e.g., traffic data, control data, and/or other data).

The PSS, SSS, CRS and PBCH in LTE are described in 3GPP TS 36.211,entitled “Evolved Universal Terrestrial Radio Access (E-UTRA); PhysicalChannels and Modulation,” which is publicly available.

An interlace structure may be used for each of the downlink and uplinkfor FDD in certain telecommunications systems (e.g., LTE). For example,Q interlaces with indices of 0 through Q−1 may be defined, where Q maybe equal to 4, 6, 8, 10, or some other value. Each interlace may includesubframes that are spaced apart by Q frames. In particular, interlace qmay include subframes q, q+Q, q+2Q, etc., where q∈[0, . . . , Q−1].

The wireless network may support hybrid automatic retransmission request(HARQ) for data transmission on the downlink and uplink. For HARQ, atransmitter (e.g., a BS) may send one or more transmissions of a packetuntil the packet is decoded correctly by a receiver (e.g., a UE) or someother termination condition is encountered. For synchronous HARQ, alltransmissions of the packet may be sent in subframes of a singleinterlace. For asynchronous HARQ, each transmission of the packet may besent in any subframe.

A UE may be located within the coverage of multiple BSs. One of theseBSs may be selected to serve the UE. The serving BS may be selectedbased on various criteria such as received signal strength, receivedsignal quality, pathloss, etc. Received signal quality may be quantifiedby a signal-to-noise-and-interference ratio (SINR), or a referencesignal received quality (RSRQ), or some other metric. The UE may operatein a dominant interference scenario in which the UE may observe highinterference from one or more interfering BS s.

Example NR/5G RAN Architecture

While aspects of the examples described herein may be associated withLTE technologies, aspects of the present disclosure may be applicablewith other wireless communications systems, such as new radio (NR) or 5Gtechnologies.

NR may refer to radios configured to operate according to a new airinterface (e.g., other than Orthogonal Frequency Divisional MultipleAccess (OFDMA)-based air interfaces) or fixed transport layer (e.g.,other than Internet Protocol (IP)). NR may utilize OFDM with a CP on theuplink and downlink and include support for half-duplex operation usingTDD. NR may include Enhanced Mobile Broadband (eMBB) service targetingwide bandwidth (e.g. 80 MHz beyond), millimeter wave (mmW) targetinghigh carrier frequency (e.g. 60 GHz), massive MTC (mMTC) targetingnon-backward compatible MTC techniques, and/or mission criticaltargeting ultra reliable low latency communications (URLLC) service.

A single component carrier bandwidth of 100 MHZ may be supported. NRresource blocks may span 12 sub-carriers with a sub-carrier bandwidth of75 kHz over a 0.1 ms duration. Each radio frame may consist of 50subframes with a length of 10 ms. Consequently, each subframe may have alength of 0.2 ms. Each subframe may indicate a link direction (i.e., DLor UL) for data transmission and the link direction for each subframemay be dynamically switched. Each subframe may include DL/UL data aswell as DL/UL control data. UL and DL subframes for NR may be asdescribed in more detail below with respect to FIGS. 7 and 8.

Beamforming may be supported and beam direction may be dynamicallyconfigured. MIMO transmissions with precoding may also be supported.MIMO configurations in the DL may support up to 8 transmit antennas withmulti-layer DL transmissions up to 8 streams and up to 2 streams per UE.Multi-layer transmissions with up to 2 streams per UE may be supported.Aggregation of multiple cells may be supported with up to 8 servingcells. Alternatively, NR may support a different air interface, otherthan an OFDM-based interface. NR networks may include entities suchcentral units or distributed units

The RAN may include a central unit (CU) and distributed units (DUs). ANR BS (e.g., gNB, 5G Node B, Node B, transmit receive point (TRP),access point (AP)) may correspond to one or multiple BSs. NR cells canbe configured as access cells (ACells) or data only cells (DCells). Forexample, the RAN (e.g., a central unit or distributed unit) canconfigure the cells. DCells may be cells used for carrier aggregation ordual connectivity, but not used for initial access, cellselection/reselection, or handover.

FIG. 5 illustrates an example logical architecture of a distributed RAN500, according to aspects of the present disclosure. A 5G access node506 may include an access node controller (ANC) 502. The ANC may be acentral unit (CU) of the distributed RAN 500. The backhaul interface tothe next generation core network (NG-CN) 504 may terminate at the ANC.The backhaul interface to neighboring next generation access nodes(NG-ANs) may terminate at the ANC. The ANC may include one or more TRPs508 (which may also be referred to as BSs, NR BSs, Node Bs, 5G NBs, APs,gNB, or some other term). As described above, a TRP may be usedinterchangeably with “cell.”

The TRPs 508 may be a distributed unit (DU). The TRPs may be connectedto one ANC (ANC 502) or more than one ANC (not illustrated). Forexample, for RAN sharing, radio as a service (RaaS), and servicespecific AND deployments, the TRP may be connected to more than one ANC.A TRP may include one or more antenna ports. The TRPs may be configuredto individually (e.g., dynamic selection) or jointly (e.g., jointtransmission) serve traffic to a UE. According to certain aspects, a BSmay include a central unit (CU) (e.g., ANC 502) and/or one or moredistributed units (e.g., one or more TRPs 508).

The local architecture 500 may be used to illustrate fronthauldefinition. The architecture may be defined that support fronthaulingsolutions across different deployment types. For example, thearchitecture may be based on transmit network capabilities (e.g.,bandwidth, latency, and/or jitter).

The architecture may share features and/or components with LTE.According to aspects, the next generation AN (NG-AN) 510 may supportdual connectivity with NR. The NG-AN may share a common fronthaul forLTE and NR.

The architecture may enable cooperation between and among TRPs 508. Forexample, cooperation may be pre-set within a TRP and/or across TRPs viathe ANC 502. According to aspects, no inter-TRP interface may beneeded/present.

According to aspects, a dynamic configuration of split logical functionsmay be present within the architecture 500. The PDCP, RLC, MAC protocolmay be adaptively placed at the ANC or TRP.

FIG. 6 illustrates an example physical architecture of a distributed RAN600, according to aspects of the present disclosure. A centralized corenetwork unit (C-CU) 602 may host core network functions. The C-CU may becentrally deployed. C-CU functionality may be offloaded (e.g., toadvanced wireless services (AWS)), in an effort to handle peak capacity.

A centralized RAN unit (C-RU) 604 may host one or more ANC functions.Optionally, the C-RU may host core network functions locally. The C-RUmay have distributed deployment. The C-RU may be closer to the networkedge.

A distributed unit (DU) 606 may host one or more TRPs. The DU may belocated at edges of the network with radio frequency (RF) functionality.

FIG. 7 is a diagram 700 showing an example of a DL-centric subframe. TheDL-centric subframe may include a control portion 702. The controlportion 702 may exist in the initial or beginning portion of theDL-centric subframe. The control portion 702 may include variousscheduling information and/or control information corresponding tovarious portions of the DL-centric subframe. In some configurations, thecontrol portion 702 may be a physical DL control channel (PDCCH), asindicated in FIG. 7. The DL-centric subframe may also include a DL dataportion 704. The DL data portion 704 may sometimes be referred to as thepayload of the DL-centric subframe. The DL data portion 704 may includethe communication resources utilized to communicate DL data from thescheduling entity (e.g., UE or BS) to the subordinate entity (e.g., UE).In some configurations, the DL data portion 704 may be a physical DLshared channel (PDSCH).

The DL-centric subframe may also include a common UL portion 706. Thecommon UL portion 706 may sometimes be referred to as an UL burst, acommon UL burst, and/or various other suitable terms. The common ULportion 706 may include feedback information corresponding to variousother portions of the DL-centric subframe. For example, the common ULportion 706 may include feedback information corresponding to thecontrol portion 702. Non-limiting examples of feedback information mayinclude an ACK signal, a NACK signal, a HARQ indicator, and/or variousother suitable types of information. The common UL portion 706 mayinclude additional or alternative information, such as informationpertaining to random access channel (RACH) procedures, schedulingrequests (SRs), and various other suitable types of information. Asillustrated in FIG. 7, the end of the DL data portion 704 may beseparated in time from the beginning of the common UL portion 706. Thistime separation may sometimes be referred to as a gap, a guard period, aguard interval, and/or various other suitable terms. This separationprovides time for the switch-over from DL communication (e.g., receptionoperation by the subordinate entity (e.g., UE)) to UL communication(e.g., transmission by the subordinate entity (e.g., UE)). One ofordinary skill in the art will understand that the foregoing is merelyone example of a DL-centric subframe and alternative structures havingsimilar features may exist without necessarily deviating from theaspects described herein.

FIG. 8 is a diagram 800 showing an example of an UL-centric subframe.The UL-centric subframe may include a control portion 802. The controlportion 802 may exist in the initial or beginning portion of theUL-centric subframe. The control portion 802 in FIG. 8 may be similar tothe control portion 802 described above with reference to FIG. 8. TheUL-centric subframe may also include an UL data portion 804. The UL dataportion 804 may sometimes be referred to as the payload of theUL-centric subframe. The UL portion may refer to the communicationresources utilized to communicate UL data from the subordinate entity(e.g., UE) to the scheduling entity (e.g., UE or BS). In someconfigurations, the control portion 802 may be a physical downlinkcontrol channel (PDCCH).

As illustrated in FIG. 8, the end of the control portion 802 may beseparated in time from the beginning of the UL data portion 804. Thistime separation may sometimes be referred to as a gap, guard period,guard interval, and/or various other suitable terms. This separationprovides time for the switch-over from DL communication (e.g., receptionoperation by the scheduling entity) to UL communication (e.g.,transmission by the scheduling entity). The UL-centric subframe may alsoinclude a common UL portion 806. The common UL portion 806 in FIG. 8 maybe similar to the common UL portion 706 described above with referenceto FIG. 7. The common UL portion 806 may additional or alternativeinclude information pertaining to channel quality indicator (CQI),sounding reference signals (SRSs), and various other suitable types ofinformation. One of ordinary skill in the art will understand that theforegoing is merely one example of an UL-centric subframe andalternative structures having similar features may exist withoutnecessarily deviating from the aspects described herein.

In some circumstances, two or more subordinate entities (e.g., UEs) maycommunicate with each other using sidelink signals. Real-worldapplications of such sidelink communications may include public safety,proximity services, UE-to-network relaying, vehicle-to-vehicle (V2V)communications, Internet of Everything (IoE) communications, IoTcommunications, mission-critical mesh, and/or various other suitableapplications. Generally, a sidelink signal may refer to a signalcommunicated from one subordinate entity (e.g., UE1) to anothersubordinate entity (e.g., UE2) without relaying that communicationthrough the scheduling entity (e.g., UE or BS), even though thescheduling entity may be utilized for scheduling and/or controlpurposes. In some examples, the sidelink signals may be communicatedusing a licensed spectrum (unlike wireless local area networks, whichtypically use an unlicensed spectrum).

In one example, a frame may include both UL centric subframes and DLcentric subframes. In this example, the ratio of UL centric subframes toDL subframes in a frame may be dynamically adjusted based on the amountof UL data and the amount of DL data that are transmitted. For example,if there is more UL data, then the ratio of UL centric subframes to DLsubframes may be increased. Conversely, if there is more DL data, thenthe ratio of UL centric subframes to DL subframes may be decreased.

Example Methods and Apparatus for Dynamic UE-Category Switching forEnhanced Idle Mode Power Savings

A user equipment (UE) or a modem may perform idle mode activities. TheUE or modem may be an Internet-of-Things (IoT) device, a narrowband IoT(NB-IoT), or other wireless communications device. The device maycommunication using long term evolution (LTE) as the access stratum oraccording to different access stratum, for example, such as new radio(NR) or 5G. The idle mode activities performed by the device may bemandated by a wireless communication standard (e.g., such as the IEEELTE standards). The idle mode activities may be different based on theUE-Category (CAT) of the device, or the UE Category of which the deviceis registered with the network.

The UE Category may define uplink and downlink capability of the UE. Inone example, the capabilities associated with the UE Category may be asdefined in TS 36.306 of the 3GPP wireless standards (e.g., Table 4.1-1for downlink and Table 4.1-2 for the uplink). Other UE Categories may bedefined by different wireless standards. For example, LTE Release-12introduces Cat 0 which may be used for IoT, NB-IoT and/or enhancedmachine type communication (eMTC) devices. As another example, LTERelease-13 introduces UE Cat-M1. UE Cat-M1 may have a DL peak rate 1Mbps, and uplink peak rate 1 Mbps, may operate according to half duplex(HD) or full duplex (FD), may use 1.4 MHz bandwidth, and a maximumtransmit power of 20 dBm or 23 dBm. These UE categories are merelyexemplary, other UE categories may be defined, and the techniques ofthis disclosure may be applied for wireless device operating accordingto and/or supporting various different UE categories (e.g., LTE-M,EC-GSM-IoT (enhanced or extended coverage GSM IoT), LPWA (low power widearea), etc.).

In some cases, activities (operations) performed according to low UEcategories may use less power than activities performed according tohigher UE categories. Idle mode activities may drain power, even forlower UE categories (e.g., CAT 1) mobile devices.

Accordingly, techniques and apparatus for reducing power consumed byidle mode UEs are desirable—while still remaining compliant to the 3GPPspecifications.

Aspects of the present disclosure relate to methods and apparatus fordynamic UE-Category switching for enhanced idle mode power savings. Forexample, UEs moving to the idle mode may switch to (e.g., drop down to)a lower UE-Category (e.g., such Cat-M1), while UEs moving to theconnected mode may switch to a higher UE-Category (e.g., referred to asa regular UE Category, for example, which may include UE categories 1and higher defined in the wireless standards).

In some cases, enhanced discontinuous reception (eDRX) and/or powersaving mode (PSM) can be used by UEs that support lower UE-categories.eDRX and PSM are features that enable very long battery lifetimes, suchas 10 years or more. eDRX may include use of extended DRX cycles thatprovide UEs with longer sleeping periods between reading paging orcontrol channels. In PSM, the UE can save power when there is nofrequent need to communicate with the device.

FIG. 9 is a flow diagram illustrating operations 900 that may beperformed, for example, by a UE (e.g., UE 120, which may be an MTC oreMTC device, IoT device, NB-IoT device, or other low cost device) fordynamic switching of the UE-Category, in accordance with certain aspectsof the present disclosure. The operations 900 may begin, at 902, the UEdetermines (e.g., by monitoring broadcast information from the cell)that a cell supports a second UE category (e.g., Cat-M1), lower than afirst UE category. At 904, while in an idle mode (e.g., after athreshold duration in the idle mode), the UE operates in the cellaccording to the first UE category (e.g., a regular UE-Category, suchCat 1 or higher). At 906, while in the idle mode, the UE takes action tooperate in the cell according to the second UE category.

As described in more detail below, the UE may initiate a switch and thenregister with the cell as the second UE category. For example, the UEmay perform an out-of-service (OOS) procedure with the cell and registerwith the cell as the second UE category. Alternatively, the UE mayregister with the cell, during an initial attach, as both the first UEcategory and the second UE category. The UE may dynamically provide anindication of a currently selected UE category. The UE can then registeras the first UE category while entering the connected mode (e.g., whileattempting to connect to the cell which may occur after receiving pagingfrom the cell) or as the second UE category when moving to the idlemode.

FIG. 10 is a flow diagram illustrating operations 1000 that may beperformed, for example, by a BS (e.g., BS 110) for dynamic switching ofUE-category, in accordance with certain aspects of the presentdisclosure. The operations 1000 may begin, at 1002, by broadcastinginformation indicating that the BS supports a second UE category (e.g.,UE Cat-M1), lower than a first UE category. At 1004, the BS receivescombined registration information registering a UE as the first UEcategory and the second UE category. The BS may receive the combinedregistration information during an initial attachment procedure. The BSmay receive an indication of a currently selected UE category. Theindication may be provided dynamically by the UE. For example, the BSmay receive registration information registering the UE as the first UEcategory along with a connection setup message from the UE and/or the BSmay receive registration information registering the UE as the second UEcategory when the UE moves to the idle mode.

Example Dynamic UE-Category Switching and Re-Registration

According to certain aspects, the UE may perform dynamic switching andre-registering with the cell as a different UE-Category.

FIG. 11 is a call flow diagram 1100 for dynamically switchingUE-Category, in accordance with certain aspects of the presentdisclosure. In aspects, the UE 1102 may support a low UE-category, suchas Cat-M1 mode of operation. The UE 1102 may operate according to afirst UE-Category, which may be a regular UE-CAT (e.g., CAT 1 orbeyond). For example, at 1110, the UE 1102 may register with BS 1104 asthe regular UE-CAT.

At 1106, the UE may receive broadcast information from the BS 1104 and,at 1108, determine that the BS 1104 supports the low UE-category (e.g.,CAT-M1) based on the broadcast information. For example, UE 1102 maymonitor the network for broadcast information (e.g., monitor thephysical broadcast channel (PBCH)). At 1106, the UE 1102 may receive thebroadcast information (e.g., master information block (MIB) and systeminformation blocks (SIBs)) from the BS 1104. Based on the broadcastinformation, the UE 1102 may determine, at 1108, that the BS 1104supports a lower UE-Category, such as Cat-M1. For example, theschedulingInfoSIB1-BR element in the MIB may indicate that the cellsupports Cat-M1.

Although shown in FIG. 11 before registering as the UE-CAT at 1100, thereceipt of the broadcast information and the determination at steps 1106and 1108 could occur at other times, such as after the registration at1110 or after the UE enters the idle mode at 1112.

At 1112, the UE may enter an idle mode. At 1114, the idle mode UE 1102may dynamically switch to a lower UE-CAT in order to enhance powersavings during the idle mode (e.g., based on the determination that theBS 1104 supports CAT M1). In some cases, the idle mode UE 1102 may waitfor a pre-configured duration (e.g., a threshold duration) in the idlemode before switching. For example, although not shown in FIG. 11, theUE could initiate a timer upon entering the idle mode and switch the UEcategory at expiry of the timer.

According to certain aspects, if the network (e.g., cell, BS 1104)supports the lower UE-category, such as Cat-M1 mode of operation, at1114, the UE 1102 may switch UE category and, at 1116, re-register asthe lower UE-Category with the network. Based on the registration forthe lower UE-category, the network may know that the UE pages are to berepeated and the paging cycle extended (e.g., using eDRX).

When the UE 1102 receives, at 1118, a page from BS 1104 that is directedto the UE (e.g., such as a mobile terminated (MT) call) or when the UE1102 initiates a call (e.g., a mobile originated (MO) call), the UE 1102may again switch UE category at 1120 (e.g., back to the original regularUE category or a different UE category). For example, at 1122, the UE1102 may re-register to the network as the higher UE-Category and thenmove to the connected state (e.g., during the call setup).

Operating according to the lower UE-category, such as Cat-M1, may resultin large idle mode power savings for the UE.

Example Dynamic UE-Category Switching Using Multiple UE-CategoryRegistration

According to certain aspects, the UE may be register with multipleUE-categories (e.g., a regular UE-CAT and Cat-M1) to enable dynamicUE-category switching.

FIG. 12 is a call flow diagram 1200 for dynamically switchingUE-Category, in accordance with certain aspects of the presentdisclosure. As shown in FIG. 12, at 1206, the UE 1202 can register withthe BS 1204 as multiple UE-categories. For example, during an initialattachment procedure with the cell, the UE 1202 may send combinedregistration information registering the UE 1202 as a regular CAT (e.g.,CAT 1 or higher) and low UE category, such as Cat-M1. Along with thecombined registration information, at 1206, UE 1202 may also indicatethe chosen category to be used henceforth (e.g., the currently selectedUE category). After the combined registration, the UE 1202 candynamically switch between the registered UE-categories. For example, at1208, the UE 1202 may receive paging from the BS 1204 and, at 1210attempt to connect to the network and move to the connected state.During the connection attempt at 1210, the UE 1202 may register as theregular UE-category, for example by sending a new message (e.g., anindication or registration information) to the network. For example, thenew message may be sent along with a connection setup message at 1210.While moving back from the connected state to the idle mode (or afterentering the idle mode, e.g., shortly after entering the idle mode) at1212, the UE may register itself as the Cat-M1 at 1214.

The methods disclosed herein comprise one or more steps or actions forachieving the described method. The method steps and/or actions may beinterchanged with one another without departing from the scope of theclaims. In other words, unless a specific order of steps or actions isspecified, the order and/or use of specific steps and/or actions may bemodified without departing from the scope of the claims.

As used herein, the term “or” is intended to mean an inclusive “or”rather than an exclusive “or.” That is, unless specified otherwise, orclear from the context, the phrase, for example, “X employs A or B” isintended to mean any of the natural inclusive permutations. That is, forexample the phrase “X employs A or B” is satisfied by any of thefollowing instances: X employs A; X employs B; or X employs both A andB. As used herein, reference to an element in the singular is notintended to mean “one and only one” unless specifically so stated, butrather “one or more.” For example, the articles “a” and “an” as used inthis application and the appended claims should generally be construedto mean “one or more” unless specified otherwise or clear from thecontext to be directed to a singular form. Unless specifically statedotherwise, the term “some” refers to one or more. As used herein, aphrase referring to “at least one of” a list of items refers to anycombination of those items, including single members. As an example, “atleast one of: a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c,and a-b-c, as well as any combination with multiples of the same element(e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c,and c-c-c or any other ordering of a, b, and c). As used herein,including in the claims, the term “and/or,” when used in a list of twoor more items, means that any one of the listed items can be employed byitself, or any combination of two or more of the listed items can beemployed. For example, if a composition is described as containingcomponents A, B, and/or C, the composition can contain A alone; B alone;C alone; A and B in combination; A and C in combination; B and C incombination; or A, B, and C in combination.

As used herein, the term “determining” encompasses a wide variety ofactions. For example, “determining” may include calculating, computing,processing, deriving, investigating, looking up (e.g., looking up in atable, a database or another data structure), ascertaining and the like.Also, “determining” may include receiving (e.g., receiving information),accessing (e.g., accessing data in a memory) and the like. Also,“determining” may include resolving, selecting, choosing, establishingand the like.

In some cases, rather than actually transmitting a frame, a device mayhave an interface to output a frame for transmission. For example, aprocessor may output a frame, via a bus interface, to an RF front endfor transmission. Similarly, rather than actually receiving a frame, adevice may have an interface to obtain a frame received from anotherdevice. For example, a processor may obtain (or receive) a frame, via abus interface, from an RF front end for transmission.

The various operations of methods described above may be performed byany suitable means capable of performing the corresponding functions.The means may include various hardware and/or software component(s)and/or module(s), including, but not limited to a circuit, anapplication specific integrated circuit (ASIC), or processor. Generally,where there are operations illustrated in figures, those operations mayhave corresponding counterpart means-plus-function components withsimilar numbering.

For example, means for determining, means for performing, means foroperating, means for transmitting, means for receiving, means forsending, means for signaling, means for selecting, means fordetermining, means for identifying, means for registering, means forattempting, means for broadcasting, means for initiating, means fortaking action, and/or means for monitoring may include one or moreprocessors or other elements, such as the transmit processor 264, thecontroller/processor 280, the receive processor 258, and/or antenna(s)252 of the user equipment 120 illustrated in FIG. 2, and/or the transmitprocessor 220, the controller/processor 240, and/or antenna(s) 234 ofthe base station 110 illustrated in FIG. 2.

The various illustrative logical blocks, modules and circuits describedin connection with the present disclosure may be implemented orperformed with a general purpose processor, a digital signal processor(DSP), an application specific integrated circuit (ASIC), a fieldprogrammable gate array (FPGA) or other programmable logic device (PLD),discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described herein.A general-purpose processor may be a microprocessor, but in thealternative, the processor may be any commercially available processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices, e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or any other suchconfiguration.

If implemented in hardware, an example hardware configuration maycomprise a processing system in a wireless node. The processing systemmay be implemented with a bus architecture. The bus may include anynumber of interconnecting buses and bridges depending on the specificapplication of the processing system and the overall design constraints.The bus may link together various circuits including a processor,machine-readable media, and a bus interface. The bus interface may beused to connect a network adapter, among other things, to the processingsystem via the bus. The network adapter may be used to implement thesignal processing functions of the PHY layer. For example, in the caseof a wireless node, a user interface (e.g., keypad, display, mouse,joystick, etc.) may also be connected to the bus. The bus may also linkvarious other circuits such as timing sources, peripherals, voltageregulators, power management circuits, and the like, which are wellknown in the art, and therefore, will not be described any further. Theprocessor may be implemented with one or more general-purpose and/orspecial-purpose processors. Examples include microprocessors,microcontrollers, DSP processors, and other circuitry that can executesoftware. Those skilled in the art will recognize how best to implementthe described functionality for the processing system depending on theparticular application and the overall design constraints imposed on theoverall system.

If implemented in software, the functions may be stored or transmittedover as one or more instructions or code on a computer-readable medium.Software shall be construed broadly to mean instructions, data, or anycombination thereof, whether referred to as software, firmware,middleware, microcode, hardware description language, or otherwise.Computer-readable media include both computer storage media andcommunication media including any medium that facilitates transfer of acomputer program from one place to another. The processor may beresponsible for managing the bus and general processing, including theexecution of software modules stored on the machine-readable storagemedia. A computer-readable storage medium may be coupled to a processorsuch that the processor can read information from, and write informationto, the storage medium. In the alternative, the storage medium may beintegral to the processor. By way of example, the machine-readable mediamay include a transmission line, a carrier wave modulated by data,and/or a computer readable storage medium with instructions storedthereon separate from the wireless node, all of which may be accessed bythe processor through the bus interface. Alternatively, or in addition,the machine-readable media, or any portion thereof, may be integratedinto the processor, such as the case may be with cache and/or generalregister files. Examples of machine-readable storage media may include,by way of example, RAM (Random Access Memory), flash memory, phasechange memory, ROM (Read Only Memory), PROM (Programmable Read-OnlyMemory), EPROM (Erasable Programmable Read-Only Memory), EEPROM(Electrically Erasable Programmable Read-Only Memory), registers,magnetic disks, optical disks, hard drives, or any other suitablestorage medium, or any combination thereof. The machine-readable mediamay be embodied in a computer-program product.

A software module may comprise a single instruction, or manyinstructions, and may be distributed over several different codesegments, among different programs, and across multiple storage media.The computer-readable media may comprise a number of software modules.The software modules include instructions that, when executed by anapparatus such as a processor, cause the processing system to performvarious functions. The software modules may include a transmissionmodule and a receiving module. Each software module may reside in asingle storage device or be distributed across multiple storage devices.By way of example, a software module may be loaded into RAM from a harddrive when a triggering event occurs. During execution of the softwaremodule, the processor may load some of the instructions into cache toincrease access speed. One or more cache lines may then be loaded into ageneral register file for execution by the processor. When referring tothe functionality of a software module below, it will be understood thatsuch functionality is implemented by the processor when executinginstructions from that software module.

Also, any connection is properly termed a computer-readable medium. Forexample, if the software is transmitted from a website, server, or otherremote source using a coaxial cable, fiber optic cable, twisted pair,digital subscriber line (DSL), or wireless technologies such as infrared(IR), radio, and microwave, then the coaxial cable, fiber optic cable,twisted pair, DSL, or wireless technologies such as infrared, radio, andmicrowave are included in the definition of medium. Disk and disc, asused herein, include compact disc (CD), laser disc, optical disc,digital versatile disc (DVD), floppy disk, and Blu-ray® disc where disksusually reproduce data magnetically, while discs reproduce dataoptically with lasers. Thus, in some aspects computer-readable media maycomprise non-transitory computer-readable media (e.g., tangible media).In addition, for other aspects computer-readable media may comprisetransitory computer-readable media (e.g., a signal). Combinations of theabove should also be included within the scope of computer-readablemedia.

Thus, certain aspects may comprise a computer program product forperforming the operations presented herein. For example, such a computerprogram product may comprise a computer-readable medium havinginstructions stored (and/or encoded) thereon, the instructions beingexecutable by one or more processors to perform the operations describedherein.

Further, it should be appreciated that modules and/or other appropriatemeans for performing the methods and techniques described herein can bedownloaded and/or otherwise obtained by a wireless node and/or basestation as applicable. For example, such a device can be coupled to aserver to facilitate the transfer of means for performing the methodsdescribed herein. Alternatively, various methods described herein can beprovided via storage means (e.g., RAM, ROM, a physical storage mediumsuch as a compact disc (CD) or floppy disk, etc.), such that a wirelessnode and/or base station can obtain the various methods upon coupling orproviding the storage means to the device. Moreover, any other suitabletechnique for providing the methods and techniques described herein to adevice can be utilized.

It is to be understood that the claims are not limited to the preciseconfiguration and components illustrated above. Various modifications,changes and variations may be made in the arrangement, operation anddetails of the methods and apparatus described above without departingfrom the scope of the claims.

What is claimed is:
 1. A method for wireless communications by a basestation (BS), comprising: broadcasting information indicating that theBS supports a second UE category, lower than a first UE category; andreceiving combined registration information registering a user equipment(UE) as the first UE category and the second UE category.
 2. The methodof claim 1, further comprising: receiving an indication from the UE ofthe first UE category or the second UE category as a currently selectedUE category.
 3. The method of claim 1, wherein the second UE categorycomprises a UE CAT M1.
 4. The method of claim 1, further comprising:sending a page to the UE; and in response to the page: receivingregistration information along with a connection setup message from theUE, the registration information re-registering the UE as the first UEcategory.
 5. The method of claim 1, further comprising: receivingregistration information re-registering the UE as the second UEcategory, wherein the UE is in an idle mode.
 6. An apparatus forwireless communications by a base station (BS), comprising: means forbroadcasting information indicating that the BS supports a second UEcategory, lower than a first UE category; and means for receivingcombined registration information registering a user equipment (UE) asthe first UE category and the second UE category.
 7. The apparatus ofclaim 6, further comprising: means for receiving an indication from theUE of the first UE category or the second UE category as a currentlyselected UE category.
 8. The apparatus of claim 6, wherein the second UEcategory comprises a UE CAT M1.
 9. The apparatus of claim 6, furthercomprising: means for sending a page to the UE; and means for, inresponse to the page: receiving registration information along with aconnection setup message from the UE, the registration informationre-registering the UE as the first UE category.
 10. The apparatus ofclaim 6, further comprising: means for receiving registrationinformation re-registering the UE as the second UE category, wherein theUE is in an idle mode.
 11. An apparatus for wireless communications by abase station (BS), comprising: at least one processor; and memorycoupled to the at least one processor, the memory including instructionsexecutable by the at least one processor to cause the apparatus to:broadcast information indicating that the BS supports a second UEcategory, lower than a first UE category; and receive combinedregistration information registering a user equipment (UE) as the firstUE category and the second UE category.
 12. A computer readable mediumhaving computer executable code stored thereon for wirelesscommunications by a base station (BS), comprising: code for broadcastinginformation indicating that the BS supports a second UE category, lowerthan a first UE category; and code for receiving combined registrationinformation registering a user equipment (UE) as the first UE categoryand the second UE category.